1. Field of the Invention
The present invention relates to a tuned array vibration absorber. Specifically, a cantilever constrained layer damping beam is formed by mounting a laminated structure in a rigid base. The dampening beam damps the vibrational kinetic energy that is traverse to its laminar layers at a discrete frequency. An array of dampening beams absorbs some of the vibrational kinetic energy and disperses the remaining vibrational kinetic energy over a broader frequency range.
2. Description of related art
Many objects vibrate at a discrete resonance frequency. It is often necessary to damp the resonance vibrations. For example, the actuator of a disk drive undergoes rapid acceleration and deceleration as it seeks its prescribed track on the disk. The sudden stopping causes the actuator to vibrate at a predetermined resonance frequency. The resonance vibrations can cause the read head to erroneously read adjacent tracks on the disk. Both the speed and accuracy of a disk drive are thus limited by the time required for the resonance vibration of the actuator to damp out.
Different techniques have been tried to damp out the resonance vibrations of the actuator coil of a disk drive. One solution moves a high density mass through grease so that fluid friction removes vibrational energy from the actuator coil. The grease dampening, however, damps all frequencies of vibration to the same extent and therefore does not discriminate in favor of the resonance vibrations.
Another solution is to make part of the structure to be damped from a vibration absorbing material. This solution has several disadvantages. It may not be practical to incorporate vibration absorbing material into a structure. The vibration absorbing material often reduces the strength of the structure because damping material is generally less rigid than the material it replaces.